/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package com.googlecode.bluetools.dom4j.dom;

import java.util.List;

import org.w3c.dom.DOMException;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.NodeList;

import com.googlecode.bluetools.dom4j.Branch;
import com.googlecode.bluetools.dom4j.CharacterData;
import com.googlecode.bluetools.dom4j.Document;
import com.googlecode.bluetools.dom4j.DocumentType;
import com.googlecode.bluetools.dom4j.Element;
import com.googlecode.bluetools.dom4j.Node;

/**
 * <p>
 * <code>DOMNodeHelper</code> contains a collection of utility methods for use across Node implementations.
 * </p>
 * 
 * @author <a href="mailto:james.strachan@metastuff.com">James Strachan </a>
 * @version $Revision: 1.1 $
 */
public class DOMNodeHelper {
	public static final NodeList EMPTY_NODE_LIST = new EmptyNodeList();

	protected DOMNodeHelper() {
	}

	// Node API
	// -------------------------------------------------------------------------
	public static boolean supports(Node node, String feature, String version) {
		return false;
	}

	public static String getNamespaceURI(Node node) {
		return null;
	}

	public static String getPrefix(Node node) {
		return null;
	}

	public static String getLocalName(Node node) {
		return null;
	}

	public static void setPrefix(Node node, String prefix) throws DOMException {
		notSupported();
	}

	public static String getNodeValue(Node node) throws DOMException {
		return node.getText();
	}

	public static void setNodeValue(Node node, String nodeValue) throws DOMException {
		node.setText(nodeValue);
	}

	public static org.w3c.dom.Node getParentNode(Node node) {
		return asDOMNode(node.getParent());
	}

	public static NodeList getChildNodes(Node node) {
		return EMPTY_NODE_LIST;
	}

	public static org.w3c.dom.Node getFirstChild(Node node) {
		return null;
	}

	public static org.w3c.dom.Node getLastChild(Node node) {
		return null;
	}

	public static org.w3c.dom.Node getPreviousSibling(Node node) {
		Element parent = node.getParent();

		if (parent != null) {
			int index = parent.indexOf(node);

			if (index > 0) {
				Node previous = parent.node(index - 1);

				return asDOMNode(previous);
			}
		}

		return null;
	}

	public static org.w3c.dom.Node getNextSibling(Node node) {
		Element parent = node.getParent();

		if (parent != null) {
			int index = parent.indexOf(node);

			if (index >= 0) {
				if (++index < parent.nodeCount()) {
					Node next = parent.node(index);

					return asDOMNode(next);
				}
			}
		}

		return null;
	}

	public static NamedNodeMap getAttributes(Node node) {
		return null;
	}

	public static org.w3c.dom.Document getOwnerDocument(Node node) {
		return asDOMDocument(node.getDocument());
	}

	public static org.w3c.dom.Node insertBefore(Node node, org.w3c.dom.Node newChild, org.w3c.dom.Node refChild)
			throws DOMException {
		if (node instanceof Branch) {
			Branch branch = (Branch) node;
			List list = branch.content();
			int index = list.indexOf(refChild);

			if (index < 0) {
				branch.add((Node) newChild);
			}
			else {
				list.add(index, newChild);
			}

			return newChild;
		}
		else {
			throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, "Children not allowed for this node: " + node);
		}
	}

	public static org.w3c.dom.Node replaceChild(Node node, org.w3c.dom.Node newChild, org.w3c.dom.Node oldChild)
			throws DOMException {
		if (node instanceof Branch) {
			Branch branch = (Branch) node;
			List list = branch.content();
			int index = list.indexOf(oldChild);

			if (index < 0) {
				throw new DOMException(DOMException.NOT_FOUND_ERR, "Tried to replace a non existing child "
						+ "for node: " + node);
			}

			list.set(index, newChild);

			return oldChild;
		}
		else {
			throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, "Children not allowed for this node: " + node);
		}
	}

	public static org.w3c.dom.Node removeChild(Node node, org.w3c.dom.Node oldChild) throws DOMException {
		if (node instanceof Branch) {
			Branch branch = (Branch) node;
			branch.remove((Node) oldChild);

			return oldChild;
		}

		throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, "Children not allowed for this node: " + node);
	}

	public static org.w3c.dom.Node appendChild(Node node, org.w3c.dom.Node newChild) throws DOMException {
		if (node instanceof Branch) {
			Branch branch = (Branch) node;
			org.w3c.dom.Node previousParent = newChild.getParentNode();

			if (previousParent != null) {
				previousParent.removeChild(newChild);
			}

			branch.add((Node) newChild);

			return newChild;
		}

		throw new DOMException(DOMException.HIERARCHY_REQUEST_ERR, "Children not allowed for this node: " + node);
	}

	public static boolean hasChildNodes(Node node) {
		return false;
	}

	public static org.w3c.dom.Node cloneNode(Node node, boolean deep) {
		return asDOMNode((Node) node.clone());
	}

	public static void normalize(Node node) {
		notSupported();
	}

	public static boolean isSupported(Node n, String feature, String version) {
		return false;
	}

	public static boolean hasAttributes(Node node) {
		if ((node != null) && node instanceof Element) {
			return ((Element) node).attributeCount() > 0;
		}
		else {
			return false;
		}
	}

	// CharacterData API
	// -------------------------------------------------------------------------
	public static String getData(CharacterData charData) throws DOMException {
		return charData.getText();
	}

	public static void setData(CharacterData charData, String data) throws DOMException {
		charData.setText(data);
	}

	public static int getLength(CharacterData charData) {
		String text = charData.getText();

		return (text != null) ? text.length() : 0;
	}

	public static String substringData(CharacterData charData, int offset, int count) throws DOMException {
		if (count < 0) {
			throw new DOMException(DOMException.INDEX_SIZE_ERR, "Illegal value for count: " + count);
		}

		String text = charData.getText();
		int length = (text != null) ? text.length() : 0;

		if ((offset < 0) || (offset >= length)) {
			throw new DOMException(DOMException.INDEX_SIZE_ERR, "No text at offset: " + offset);
		}

		if ((offset + count) > length) {
			return text.substring(offset);
		}

		return text.substring(offset, offset + count);
	}

	public static void appendData(CharacterData charData, String arg) throws DOMException {
		if (charData.isReadOnly()) {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, "CharacterData node is read only: "
					+ charData);
		}
		else {
			String text = charData.getText();

			if (text == null) {
				charData.setText(text);
			}
			else {
				charData.setText(text + arg);
			}
		}
	}

	public static void insertData(CharacterData data, int offset, String arg) throws DOMException {
		if (data.isReadOnly()) {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, "CharacterData node is read only: " + data);
		}
		else {
			String text = data.getText();

			if (text == null) {
				data.setText(arg);
			}
			else {
				int length = text.length();

				if ((offset < 0) || (offset > length)) {
					throw new DOMException(DOMException.INDEX_SIZE_ERR, "No text at offset: " + offset);
				}
				else {
					StringBuffer buffer = new StringBuffer(text);
					buffer.insert(offset, arg);
					data.setText(buffer.toString());
				}
			}
		}
	}

	public static void deleteData(CharacterData charData, int offset, int count) throws DOMException {
		if (charData.isReadOnly()) {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, "CharacterData node is read only: "
					+ charData);
		}
		else {
			if (count < 0) {
				throw new DOMException(DOMException.INDEX_SIZE_ERR, "Illegal value for count: " + count);
			}

			String text = charData.getText();

			if (text != null) {
				int length = text.length();

				if ((offset < 0) || (offset >= length)) {
					throw new DOMException(DOMException.INDEX_SIZE_ERR, "No text at offset: " + offset);
				}
				else {
					StringBuffer buffer = new StringBuffer(text);
					buffer.delete(offset, offset + count);
					charData.setText(buffer.toString());
				}
			}
		}
	}

	public static void replaceData(CharacterData charData, int offset, int count, String arg) throws DOMException {
		if (charData.isReadOnly()) {
			throw new DOMException(DOMException.NO_MODIFICATION_ALLOWED_ERR, "CharacterData node is read only: "
					+ charData);
		}
		else {
			if (count < 0) {
				throw new DOMException(DOMException.INDEX_SIZE_ERR, "Illegal value for count: " + count);
			}

			String text = charData.getText();

			if (text != null) {
				int length = text.length();

				if ((offset < 0) || (offset >= length)) {
					throw new DOMException(DOMException.INDEX_SIZE_ERR, "No text at offset: " + offset);
				}
				else {
					StringBuffer buffer = new StringBuffer(text);
					buffer.replace(offset, offset + count, arg);
					charData.setText(buffer.toString());
				}
			}
		}
	}

	// Branch API
	// -------------------------------------------------------------------------
	public static void appendElementsByTagName(List list, Branch parent, String name) {
		final boolean isStar = "*".equals(name);

		for (int i = 0, size = parent.nodeCount(); i < size; i++) {
			Node node = parent.node(i);

			if (node instanceof Element) {
				Element element = (Element) node;

				if (isStar || name.equals(element.getName())) {
					list.add(element);
				}

				appendElementsByTagName(list, element, name);
			}
		}
	}

	public static void appendElementsByTagNameNS(List list, Branch parent, String namespace, String localName) {
		final boolean isStarNS = "*".equals(namespace);
		final boolean isStar = "*".equals(localName);

		for (int i = 0, size = parent.nodeCount(); i < size; i++) {
			Node node = parent.node(i);

			if (node instanceof Element) {
				Element element = (Element) node;

				if ((isStarNS
						|| (((namespace == null) || (namespace.length() == 0)) && ((element.getNamespaceURI() == null) || (element
								.getNamespaceURI().length() == 0))) || ((namespace != null) && namespace.equals(element
						.getNamespaceURI())))
						&& (isStar || localName.equals(element.getName()))) {
					list.add(element);
				}

				appendElementsByTagNameNS(list, element, namespace, localName);
			}
		}
	}

	// Helper methods
	// -------------------------------------------------------------------------
	public static NodeList createNodeList(final List list) {
		return new NodeList() {
			public org.w3c.dom.Node item(int index) {
				if (index >= getLength()) {
					/*
					 * From the NodeList specification: If index is greater than or equal to the number of nodes in the
					 * list, this returns null.
					 */
					return null;
				}
				else {
					return DOMNodeHelper.asDOMNode((Node) list.get(index));
				}
			}

			public int getLength() {
				return list.size();
			}
		};
	}

	public static org.w3c.dom.Node asDOMNode(Node node) {
		if (node == null) {
			return null;
		}

		if (node instanceof org.w3c.dom.Node) {
			return (org.w3c.dom.Node) node;
		}
		else {
			// Use DOMWriter?
			System.out.println("Cannot convert: " + node + " into a W3C DOM Node");
			notSupported();

			return null;
		}
	}

	public static org.w3c.dom.Document asDOMDocument(Document document) {
		if (document == null) {
			return null;
		}

		if (document instanceof org.w3c.dom.Document) {
			return (org.w3c.dom.Document) document;
		}
		else {
			// Use DOMWriter?
			notSupported();

			return null;
		}
	}

	public static org.w3c.dom.DocumentType asDOMDocumentType(DocumentType dt) {
		if (dt == null) {
			return null;
		}

		if (dt instanceof org.w3c.dom.DocumentType) {
			return (org.w3c.dom.DocumentType) dt;
		}
		else {
			// Use DOMWriter?
			notSupported();

			return null;
		}
	}

	public static org.w3c.dom.Text asDOMText(CharacterData text) {
		if (text == null) {
			return null;
		}

		if (text instanceof org.w3c.dom.Text) {
			return (org.w3c.dom.Text) text;
		}
		else {
			// Use DOMWriter?
			notSupported();

			return null;
		}
	}

	public static org.w3c.dom.Element asDOMElement(Node element) {
		if (element == null) {
			return null;
		}

		if (element instanceof org.w3c.dom.Element) {
			return (org.w3c.dom.Element) element;
		}
		else {
			// Use DOMWriter?
			notSupported();

			return null;
		}
	}

	public static org.w3c.dom.Attr asDOMAttr(Node attribute) {
		if (attribute == null) {
			return null;
		}

		if (attribute instanceof org.w3c.dom.Attr) {
			return (org.w3c.dom.Attr) attribute;
		}
		else {
			// Use DOMWriter?
			notSupported();

			return null;
		}
	}

	/**
	 * Called when a method has not been implemented yet
	 * 
	 * @throws DOMException DOCUMENT ME!
	 */
	public static void notSupported() {
		throw new DOMException(DOMException.NOT_SUPPORTED_ERR, "Not supported yet");
	}

	public static class EmptyNodeList implements NodeList {
		public org.w3c.dom.Node item(int index) {
			return null;
		}

		public int getLength() {
			return 0;
		}
	}
}

/*
 * Redistribution and use of this software and associated documentation ("Software"), with or without modification, are
 * permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and notices. Redistributions must also contain a
 * copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
 * following disclaimer in the documentation and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived from this Software without prior written
 * permission of MetaStuff, Ltd. For written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may "DOM4J" appear in their names without prior
 * written permission of MetaStuff, Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
